#region The MIT License
// The MIT License
// 
// Copyright (c) 2009 octalforty studios
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#endregion
using System.Data;

using octalforty.Wizardby.Console.Deployment;
using octalforty.Wizardby.Console.Properties;
using octalforty.Wizardby.Core.Db;
using octalforty.Wizardby.Core.Migration;

namespace octalforty.Wizardby.Console.Commands
{
    public abstract class GuardedMigrationCommandBase : MigrationCommandBase
    {
        private const string AllowDowngrade = "allow-downgrade";

        protected override void InternalExecute(MigrationParameters parameters)
        {
            IEnvironment environment = ServiceProvider.GetService<IEnvironment>();
            if(environment.Properties[AllowDowngrade] != null)
            {
                bool allowDowngrade = bool.Parse(environment.Properties[AllowDowngrade].ToLowerInvariant());
                if(!allowDowngrade)
                {
                    IMigrationVersionInfoManager migrationVersionInfoManager =
                        ServiceProvider.GetService<IMigrationVersionInfoManager>();
                    long currentMigrationVersion = DbUtil.ExecuteInTransaction<long>(ServiceProvider.GetService<IDbPlatform>(),
                        parameters.ConnectionString, delegate(IDbTransaction transaction)
                            {
                                return migrationVersionInfoManager.GetCurrentMigrationVersion(transaction);
                            });

                    if(parameters.Command == MigrationCommand.Downgrade || parameters.Command == MigrationCommand.Redo ||
                        parameters.Command == MigrationCommand.Rollback || 
                        (parameters.Command == MigrationCommand.Migrate && parameters.VersionOrStep < currentMigrationVersion))
                    {
                        throw new MigrationException(string.Format(Resources.EnvironmentDoesNotAllowDowngrades,
                            parameters.Environment, AllowDowngrade));
                    } // if
                } // if
            } // if

            InternalGuardedExecute(parameters);
        }

        protected abstract void InternalGuardedExecute(MigrationParameters parameters);
    }
}
